"Hartsfield-Jackson remains the busiest airport in the world in terms of passengers and operations," Louis Miller, the airport's general manager, said in a statement. "In addition to the airport amenities and services which appeal to many travelers, the city of Atlanta has established itself as an attractive environment in which to do business."

While passenger traffic was up in 2012, the airport's annual air cargo decreased by 2.52 percent. Smith said the numbers reflect a global decrease in purchases and reduced manufacturing.